Molecular phylogenetic analysis of "pirate spiders" (Araneae, Mimetidae) with the description of a new African genus and the first report of maternal care in the family.

Abstract

We investigate the phylogeny of "pirate spiders" (Mimetidae), a family of araneophagic spiders known for their use of aggressive mimicry as a foraging strategy, but poorly understood phylogenetically. Relationships are inferred by including molecular data from six loci for 92 mimetid terminals spanning four genera, and 119 outgroups representing 12 families. Phylogenetic analyses based on parsimony, maximum-likelihood and Bayesian approaches, as well as static and dynamic homology, robustly support monophyly of Mimetidae and a sister-group relationship to a clade comprising Tetragnathidae+Arkyidae. Relationships among the mimetid genera are largely congruent across methods, as follows: (Gelanor (Ero (Anansi n. gen. (Australomimetus, Mimetus)))). Diversification of Mimetidae is estimated to be around 114Ma, in the Early Cretaceous. In light of the results of our phylogenetic analyses, we erect Anansi n. gen. to include a clade of mimetids from West Africa that contains at least four species, including the newly described A.luki n. sp. We present the first report of maternal care in Mimetidae based on novel field observations.